This disclosure provides a method, performed in a modulation and coding scheme, MCS module of a network node, for modulation and coding scheme, MCS, selection for a link between the network node and a terminal device in an orthogonal frequency division multiple access, OFDMA, based system. The OFDMA-based system provides a plurality of sub-carriers. The method comprises obtaining channel quality indicators for the plurality of sub-carriers, and estimating a link quality over a bandwidth corresponding to the plurality of sub-carriers based on the obtained channel quality indicators. The method comprises selecting a sub-carrier out of the plurality of sub-carriers as a new sub-carrier to be used for a communication to/from the terminal device based on the determined link quality. The method comprises selecting a MCS for the new sub-carrier; and transmitting information to the terminal device, the information comprising an indication of a new sub-carrier to the terminal device.